Method for the load-free opening of a separating clutch

Abstract

A method is provided for the load-free opening of a separating clutch. The method includes the following steps: receiving a signal for disengaging the clutch; applying a negative torque at the separating clutch using a drive machine; applying a positive, predefined torque at the separating clutch using the drive machine; and opening the separating clutch as soon as the amount of the torque applied at the separating clutch lies within predefined limit values. In other words, a torque in the known range of the system is set via a drive-side deceleration. Then, a drive-side acceleration takes place, so that the torque is increased on the drive side, starting from the known range of the system, until it generally matches the torque on the output side. This enables a load-free opening of the clutch.

What is claimed is: 
     
       1. A method for the load-free opening of a separating clutch, comprising:
 receiving a signal for disengaging the separating clutch; 
 applying a negative torque at the separating clutch by a drive machine,
 wherein the negative torque is set by one of a free running of the drive machine or by an active short-circuit of the drive machine, the negative torque being smaller than a torque of an output side; 
 
 applying a positive, predefined torque at the separating clutch by the drive machine, the positive torque being greater than the torque of the output side; and 
 opening the separating clutch as soon as an amount of the torque applied at the separating clutch lies within predefined limit values. 
 
     
     
       2. The method as recited in  claim 1 , wherein the positive predefined torque is applied following a predefined time interval after applying the negative torque. 
     
     
       3. The method as recited in  claim 1 , further comprising:
 detecting a rotational speed of the drive machine; 
 applying the negative torque by an active short-circuit of the drive machine in the event that the detected rotational speed is greater than a threshold value; and 
 applying the negative torque by a switch to free running operation of the drive machine in the event that the detected rotational speed is less than the threshold value. 
 
     
     
       4. A control unit for actuating a separating clutch, wherein the control unit is configured to receive a signal for disengaging the separating clutch, to actuate a drive machine connected to the separating clutch in such a way that a negative torque is applied at the separating clutch, wherein the negative torque is set by one of a free running of the drive machine or by an active short-circuit of the drive machine, the negative torque being smaller than the torque of the output side, to actuate the drive machine connected to the separating clutch in such a way that a positive torque is applied at the separating clutch following a predefined time interval, the positive torque being greater than the torque of the output side, and to open the separating clutch as soon as an amount of the torque applied at the separating clutch lies within predefined limit values. 
     
     
       5. The control unit as recited in  claim 4 , wherein the control unit is configured to compare an instantaneous actual rotational speed of the drive machine to a threshold value. 
     
     
       6. A computer storage medium storing a computer program for a load-free opening of a separating clutch, the computer program, when executed by a processor, causing the processor to perform the steps of:
 receiving a signal for disengaging the separating clutch; 
 applying a negative torque at the separating clutch by a drive machine, 
 wherein the negative torque is set by one of a free running of the drive machine or by an active short-circuit of the drive machine, the negative torque being smaller than a torque of an output side; 
 applying a positive, predefined torque at the separating clutch by the drive machine, the positive torque being greater than the torque of the output side; and 
 opening the separating clutch as soon as the amount of the torque applied at the separating clutch lies within predefined limit values. 
 
     
     
       7. A processor containing a stored computer program for a load-free opening of a separating clutch, the computer program, when executed by a processor, causing the processor to perform the steps of:
 receiving a signal for disengaging the separating clutch; 
 applying a negative torque at the separating clutch by a drive machine, 
 wherein the negative torque is set by one of a free running of the drive machine or by an active short-circuit of the drive machine, the negative torque being smaller than a torque of an output side; 
 applying a positive, predefined torque at the separating clutch by the drive machine, the positive torque being greater than the torque of the output side; and 
 opening the separating clutch as soon as the amount of the torque applied at the separating clutch lies within predefined limit values.